Water flow detector



Dec. 27, 1960 Filed D90. 31, 1958 TRANSMITTER 2 Sheets-Sheet 1 Dec. 27,1960 A. B. HUBE WATER FLOW DETECTOR Filed Dec. 31, 1958 2 Sheets-Sheet 2United States Patent Oflfice 2,966,133 Patented Dec. 27, 1960 WATER FLOWDETECTOR Arthur B. Hube, Huntington Station, N.Y., assignor to AmericanDistrict Telegraph Company, Jersey City, N.I., a corporation of NewJersey Filed Dec. 31, 1958, Ser. No. 784,372

5 Claims. (Cl. 116-117) larly, to a vane mechanism for use in such asignaling device.

In closed fluid systems, such as sprinkler systems used forfire-protection purposes in factories, stores, warehouses, and the like,signaling devices are used to communicate abnormal or emergencyconditions to a central oflice or station. In such a system, fluidconduits or pipes, each provided with a plurality of sprinkler headsspaced at intervals along the fluid conduit, are connected to a pressurefluid supply, each of the sprinkler heads being held in a closedposition by a temperature sensitive element. Under normal conditions,the fluid in the conduit is static, that is, there is little, if any,fluid flow.

Each of the sprinkler heads in the system acts independently of theother sprinkler heads and serves as an independent fire extinguisher forthat portion of the building its spray will cover. When a fire occurs inthe vicinity of a particular sprinkler head, the element on theparticular head operates to open the head and allow fluid from theconduit to spray the area to extinguish the fire. This, of course,causes a sudden flow of fluid in the system from the pressure supplysource. Once the spray head is opened, the fluid will continue to flowuntil the head is replaced, or the system is turned off, even after thefire is extinguished.

The type of building usually provided with a sprinkler system is onewhich is occupied only during a part of the day or in which large areasare unattended. Hence, a signaling device to detect emergency orabnormal conditions in the fluid system, such as those resulting from afire or a leak in the system, and to communicate such conditions to acentral, attended oflice, is desirable.

One type of signaling device in use in such systems employs a vanepivotally mounted in a fluid conduit of the system, the vane beingconnected to a transmitter to transmit an electrical impulse to an alarmat a central station when abnormal conditions occur in the system. Inorder that the vane not impede the fluid flow through the system when asprinkler head is opened and, at the same time, to maintain the vane ina plane perpendicular to the fluid path when the sprinkler heads areclosed, such vanes have been provided with a hinged joint, the hingedjoint being biased by a spring or other metallic means to maintain thevane perpendicular to the fluid conduit when the fluid in the system isstatic but allowing the vane to be pivoted out of the fluid path whenabnormal flow occurs. Because of prolonged exposure to fluid suchmetallic means are subject to corrosion, and the like, require frequentinspections and have not been completely satisfactory.

It is the object of the present invention to provide an improved vanefor installation in a fluid flow system as a fluid flow detector for usewith a signaling system.

It is a further object of the invention to provide a vane for use withsuch a device which will render the device responsive to abnormal flowconditions, such as those caused by a fire or leak, withoutsubstantially impeding the fluid flow. V

A further object of the invention is to provide a vane for use with sucha device which may be readily installed and removed.

A still further object is to provide a vane which will automaticallyreset itself for subsequent operation after abnormal fluid flow hasabated.

Other and further objects, features and advantages of the invention willappear more fully from the following description and the accompanyingdrawings in which:

Fig. l is a side View, partly in section, of a vane mechanism inaccordance with the present invention for use in a signaling device;

Fig. 2 is a front elevational View, partly in section, of the device ofFig. 1;

Fig. 3 is a fragmentary view of the vane in section on the line 3-3 ofFig. 2.

Referring now to Figs. 1 and 2, a housing 10, having a lower flange 12and an upper flange 14 is mounted over an opening in and attached topipe or conduit 16 by means of a U-bolt as shown in Fig. 2, a gasket 18being positioned between the flange 12 and conduit 16 to provide afluid-tight connection.

A bell-shaped sleeve 22, having a threaded end 24 is fitted into thehousing 10 and is connected thereto by spreading the lower edge 26outward, by welding or brazing or by any other suitable manner. Thesleeve 22 is threaded at 28 to receive a collar 30, a gasket or seal 32being first installed in an annular recess 20 formed A cap 34, having anopening 36, is threaded onto the sleeve 22 at the threaded end 24, aretaining ring 37 and a gasket or seal 38 being positioned between thecap 34 and sleeve 22 to provide a Water-tight connection.

An operating stem 40, pivotally supported by seal 38, is connected nearits upper end 42 to one end of a spring 44 and is provided at its lowerend with a socket 46. The spring 44 is connected at its other end to ascrew 48 adjustably positioned in a support 50 on the fixed member 52.At its upper end 42, the operating stem 40 extends into a transmitter 54and is positioned adjacent a plunger 55 of a retard mechanism 56 of atype in common use in devices of this nature, the retard mechanism 56being set to close the contacts 57 a predetermined.

vane 60 is held in spaced position on the pin 64 by spacers 65.

Referring now to Figs. 2 and 3, the vane 60 comprises a flexible web 70and semi-rigid ribs 72 integrally formed therewith, the semi-rigid ribsextending from the hub 62 outwardly along the flexible web 70. The hub62, web 70 and ribs 72 are formed as a single unit of the same material,the flexibility of the web and semirigidity of the ribs being attainedthrough a variation in the relative thickness between the web and ribs.Both the web 70 and semi-rigid ribs 72 are resilient, that is, when theweb and ribs are released after having been deflected or bent they willreturn to their initial position. It is preferred to form the vane 60from a plastic material and polyethylene has been found suitable forthis purpose.

In operation, the vane 60 is positioned vertically in a feed linebetween the main water supply, such as a municipal water supply, and thesprinkler heads, the main water supply being to the right of the vane,as shown in Fig.- 1, and the sprinkler heads being to the left, waterflow caused by the opening of the sprinkler heads being in the directionof the arrow in Fig. ,1. Due to the resiliency of the web' and the ribs,the vane60 can be deformed sufliciently for insertion into andwithdrawal from the conduit 16 through the opening in the conduit,allowing the device to be readily removed for inspection. When in place,the Web 70 and ribs 72 will readily return to their normal position.With the device in position, the spring 44 is adjusted to position thestem 40 and vane 60 vertically in the housing and conduit 16,respectively. 1 e

With all of the sprinkler heads closed there will be no flow in theconduit 16 and, under usual conditions, the pressure in the conduit onthe right and left sides of the vane 60, as shown in Fig. 1, will beequal. Under such condition the web 70 and ribs 72 substantially closethe conduit. r f

As aforestated, when connected to-a municipal water supply, the systemis subject to minor flows of short duration due to fluctuations inmunicipal supply and it is desirable that such minor flows not betransmitted to the signaling device. In the device of the invention,when niinor fluctuations occur, the vane 60 pivots the stem 40 therebyexpanding the spring 44 and moving the upper end- 42 of the stem 40 awayfrom the plunger 55 freeing the retard mechanism 56 to move at a rategoverned by its adjustment. Because of the clearance in the conduit 16around the vane 60 and the flexibility of the web 70, particularly atits marginal edges, fluid passes from one side of the vane to the otherside until the pressure on the opposite sides of the vane equalizes.Since such fluctuations are only slight and of short duration,equalization of the pressure on the opposite sides of the vane is rapidand the spring 44 returns the stem 40 and vane 60 to the verticalposition against the plunger 55, as shown in Fig. 1, resetting theretard mechanism 56 before it has moved a suflicient distance to closethe contacts 57 to actuate the alarm. Each time a fluctuation occurs inthe supply the vane 60 pivots, allowing sufl'icient flow to rebalancethe system on the'opposite sides of the vane and, thereafter, the vanereturns to its original vertical position. As aforestated, the flowrequired to rebalance the system is only minor and, due to the action ofthe retard mechanism, is accomplished without actuating the alarm.

When one or more sprinkler heads are opened, fluid is exhausted from theleft of the vane, as shown in Fig. l, causing a continuous flow of fluidfrom the right to the left of the vane. stem 40 pivot in the housing 10moving the upper end 42 of the stem away from the plunger 55 therebyfreeing the retard mechanism 56 to move at its pre-adjusted rate untilthe contacts 57-are closed causing the'transmitter, through the leads58, to actuate the signal in the central station. As the vane 60 pivots,the hub 62 cont-acts the lower end of the housing 10 thereby limitingthe pivotal movement of the stem 40 at its upper end 42. However, sincethe ribs 72 are semi-rigid, they bend under the 'force of'tlie waterand, withthe flexible web 70, are

forced against the inner wall of the conduit 16, as shown in dottedlines in Fig. 2, thereby allowing unimpeded flow of fluid. The resilientvane 60 is held by the force of the water against the inner wall of theconduit until the fluid flow. is shut off.

As this flow occurs, the vane 60 and When the sprinkler heads arereplaced or the fluid flow otherwise stopped, the resilient vanestraightens and, under the influence of spring 44, the stem 40, togetherwith vane 60, is returned to its unactuated vertical position in theconduit. The signal device is then reset for subsequent operation inresponse to flow in the system.

As used herein and in the claims, the term flexible, when used inconnection with-'the web, connotes the characteristicsof thisportion ofthe vane to bend or deflect with minor flow, such as caused by slightvariations in pressure, and the term semi-rigid, when used in connectionwith the ribs, connotes the characteristi'c of this portion of the vaneto remain rigid during minor flow but to bend or deflect upon theoccurrence of a substantial flow along the conduit. Due to theresiliency of the web and the ribs, the vane will, in and of itself andwithout application of an external force, return to its undeflectedcondition when the fluid in the system returns to a static state. a i

The terms and expressions which have been employed are used as termsofdescn'ption and not oflimitation, and there is no intention, in theuse of such terms and expressions, of excluding'any equivalents ofthefeaturcs shown and described or portions thereof, but it isrecognized that various modifications are possible within the scope ofthe invention claimed. 7

What is claimed is:

1. A flow detector for a fluid conduit, comprisinga vane in saidconduit, said vane having an area slightlysmaller than that of saidconduit cross section, a support adjacent said conduit, said vane havingan extended hub portion, said hub portion being intermediately pivotedon said support ona joint transverse to the longitudinal axis of saidconduit, a-signal circuit having a switch therein, an operating stempivotallymounted on said support, one end of said stem having operativeengagement with said switch and .the other end of said stem havingengagement 'with said hub portion.

2. A flow detector as defined in claim 1, saidjvane being formed ofplastic material with the body portion thereof in said conduit beingresilient and said hub portion being rigid.

3. A flow detector as defined in claim 2, said hub portion extending insaid support and being free for' limited rotation about its pivot insaid housing, initial rotation of said vane about said hub portion pivotin' response to a predetermined rate of fluid flow causing rotation ofsaid hub portion to its extreme'position and rotation of said stem tooperate said switch while the body portion of said vane remainssubstantially unde-v across said body portion in mutually divergentrelation away from said hub portion.

References Cited the file of this patent UNITED STATES PATENTS 384,570Grovesteen June 12, 1888 1,830,673 Noren Nov. 3, 1931 1,903,713

Baule Apr. 11, 1933

